Sash-balance.



UNITED STATES PATENT onnron.

GEORGE H. FOR-SYTH, OF CHICAGO, ILLINOIS, ASSIGNOR TO FORSYTH BROTHERS COMPANY, OF CI-IIGAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

SASI-I-BALANCE.

Specification of Letters Patent.

Patented July 14, 1914.

Application filed November 19, 1906. Serial No. 344,033.

To all whom it may concern Be it known that I, GEORGE H. FORsYTH, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Sash-Balances, of which the following is a specification.

This invention relates to sash balances and more particularly to sash balances of that type'wherein an actuating spring or weight constituting the power agent of the device is wound up or tensioned by the downward movement of the sash so, as to counteract the gravity of the latter .and raise or assist in raising the sash when the latter is free to move upwardly.

It is the object of the invention to produce a simple and efficient device of this character compactly arranged and assembled in a manner to economize space; to so organize the parts that the stresses are equalized in and through the mechanism of the balance itself, preferably in the spring and its connections, so as to pull equally and uniformly on both sides of the sash; and to provide an improved device wherein the spring may be tensioned without requiring the removal of the sash from its guides.

My invention has been more particularly designed for use in connection with the windows of railway cars and especially those employing hollow sheet metal window sash; although it will be evident that the device is capable of general application and to sash of any type of construction.

In one arrangement and disposition of the device the sash balance is carried by the upper transverse bar of the sash, and opcrates through the agency of rack bars diagonally disposed on the sash guides cooperating with spring or weight-actuated .gears or pinions on the opposite ends of the sash balance spindle. the invention, however, the balance may be otherwise connected to the sash; and in all forms it operates to automatically counteract any lack of uniformity or equality of strain in the sash connections.

My invention is capable of employing torsion springs of either relatively large or small diameter, according to the spacepermitted therefor by the window casing, by a simple interchangeability in the relative diameters of the springs and the gears or pinions through which the torsional effect of In another application of the springs is transmitted to the racks of the guides.

My invention will be readily understood when considered in connection with the accompanying drawings, showing practical mechanical embodiments thereof, in which,

Figures 1 and 2 are vertical sectional views through the upper portion of the window sash and the superimposed sash balance; said views differing only in showing different modes of connection between the casing preferably employed in connection with sash balances and the upper transverse bar ofthe sash; Fig. 3 is a side elevational view of the parts shown in Fig. 2; Fig. 4 is a plan View, enlarged, of one form of sash balance, in section through the casing of the balance and the guides thereof; Fig. 5is a detail fragmentary view in elevation of the means for tensioning the spring of Fig. 4:; Fig. 6 is a view similar to Fig. l of a modified construction of sash balance; Fig. 7 is a group view in end elevation of individual parts em-' ployed in the mechanism of Fig. 6; Fig. 8 is an elevational view of a simple form of the invention, showing other devices for connec-.

tion to the sash; and Fig. 9 is an edge view ofFig. 8.

Referring first to Figs. 1 to 5, inclusive, 10 may designate the vertical angle-strips formbetween them the lateral guides of a hollow sheet metal sash indicated at 11. 12 indicates in Fig. 1 a rectangular sheet metal casing for the sash balance shown as formed integral with the upper transverse bar of the sash and superposed thereon, said casing being also indicated as of somewhat greater width than the width of the sash bar andis guided at its ends constituting superposed continuations of the guide-strips 10. In Figs. 2 and 3 the sash balance casing, instead of being formed integral with the upper transverse bar of the sash, is made separate and is attached to said bar by means of depending integral tongues 14 passed through spaced apertures in the top of the bar and secured by connecting-strips 15 and a screw-bolt 16.

Referring now to the constructional features of the'balance proper shown in detail in Figs. 4: and 5', 17 designates as an em tirety a spindle in the casing 12, said spindle carrying on its opposite ends pinions 18 meshing withdiagonally disposed vertical rack-bars 19 secured to or integral with cor by verticalanglest-rips 13 responding transverse diagonally disposed pinions 18 are'directly mounted, an intermediate section 17, and an enlarged spring S p-porting section 17 between the sections E and provided on their inner opposed faces with The sections 17 and 17, are

disks 20 and 21, respectively, to the inner faces of which are attached the opposite ends at :the coiled torsion spring-22 said spring encircling the intermediate guiding;

and supporting section of the spindle 17 which is looslyjor rotata-bly supported at itsends in the'opp'osed faces of the disks 20 ai'1d21'. Fast on the opposite end of the intermediate section .17 of the spindle is a conical worm-wheel 28 engaged bya worm. 24Fdisp0sedtransversely thereof, said worm being partially housed in a recess in the ad jacent face of a disk or block 25 carriedby theadjacent end ofthe endsection 17? of the spindle, whereby saidworm forms in effeet a'. coupling between the sections 1'? and 17? of the spindle, causing said sections to rotate together in the operation of the balmice, but permitting a relativedturning movement therebetween by. turning the Worm, forwvhic'h latter purpose the outer face'of the Worm is provided with a transverse 1 roove 26,;pand to permitthe applica-'.

tion-1o a screw driverthereto, the inner side of the .dislr25 is cut away sufficiently, as in dicated at 27 ig. By virtue of the fact sides of the" end guides of the balance case that the gears 18 engage racks on opposite ing,ian upward or downwardmovement of the latter accompanying the raising or low ering of the Window imparts rotation in 0}).- posite'directionjs to the spindle section 17? i on the one hand and the coupled sections 17 a and 17 on the other hand, which, in'the arra'ngement SlIOWD WIHClS up or tensions the spring 22 on the downward-movement of the window, the reaction 01 torsional expansion of the spring imparting a climbing etl'ectto the panions whenthe sash moves upwardly,

thereby, raising orassistingin raising the sash, The s de wall of the casing'is providedwith an opening 28 for a screw-driver I opposite tlie'.t'ront end of the worm 24,

through which the spring-may be readily tensioned. to the necessary extent by simply tur 'iii gc'the screw; v

The same general principleofsash balance is carried out in the somewhatmodified construcconstruction a sectional spindle designated as an entirety by 29 is also employed, the endsections connected-to the gears 18 being designated by 29 and 29 med-'iate's'eotion being designated by 29, and the spring guiding andsupporting section being designated by 29 the ends of -the latter section being loosely. mounted in tion illustrated in Figs. 6-.and 7".-- In this;

the main interpinion 31' rotatively mounted in a suitable bearing bracket 82 secured to theside wall of the casing, said pinion 81 having in its outer new groove 33 for the'applica tion ofa screw-drivensaid groove being located opposite a registering aperture 34: in the wall of the casing. Embracing the sec-' tion 29 and liaving'iits end'ssecured in the sections, 29 and 29 is atorsionlspring 35. The. sections- 29 and 29 of the spindle are detachably coupled so as to permititen'sion-- ing of the spring when desired without re-- moval from the casing, by the-followingnieans. Pinned or keyed tothe'inner end of the spindle section 29 is a sleeve 36}, the buter portion whereost is-externally-squared, as shown at 36 (Fig. 7), while its inner portion is externally circular, as shown at 36"; ,An externally squaredsle'ewe 37 surrounds and is pinned or keyed; to the'meeting end of the spindle sect'ionl29". Slidably mounted upon the sleeves 3.6 find 37' is a squared sleeve 38 provided with an annular peripheral groove 38%. -A' compression spring 39 surrounding the sleeve 37 hearsat hne end against-a bearing 18? andzby contact with the adjacent end of the sleeve 38 Y tends to force the {same over the squared por-' tion 36? of theQsleeve 36,. whereby the secionsj29 and 29 ofthe spindle are-normally eoupled. A slot 40 is formed inpthe side wall of the casing opposite the groove 38*, p0 that by insertingasuitable tooltherehrough into engagement with'the-sl'ot 38 the sleeve 38-inay he slid inwardly againstthe spring 39 until its outer end disengages the squaredportion 36? and engages the rounded portion 36 of the sleeve 86, whereup o n by simultaneously applying a screwdriver to the pinion 3.1,Ithe spring i nay be tensioned to the desired strength. UponreleasingthesleeveBS, thespring '39v at once forces ,it into; coupling engagement with the squared portionof the:

Integral with for fasten fcotiperating sleeve 86, thereby reestablish:

ing the continuity of the spindle. In its manner of operation this formpfbalance is identical with that already described and shown in Figs. at and '5, t-hedownward move- 1 ment of the sash tending to wind up or ten-- sion the spring 35; the expanding movement 7 of said spring taking place during and par tially or wholly effecting the opposite or rising movement of the sash.

In Figs. 8 and 9 I have illustratedanother embodiment of the principle of the invention which permits a considerable Sim-- plification of the mechanism, but which embodies the features of the'equaliz'ation fthe.

stresses at'both ends of'thebala'nce. by dis,-' tributing the same through the spring and its connections. In this "embodiment; ll"

- pull on both may designate the opposing sides of the frame or casing, to which are secured supporting brackets 42 and 4:3, the former of which has a sockets st forming a bearing for one end of a spindle 4L5, the other bracket 4C3 having a similar socket open on its up per side, as indicated at 46, to admit the other end of the spindle. Loose on the spin dle 45 at its opposite ends are pulleys 4:7, to which are secured straps 4:8 adapted to be oppositely wound thereon, and connected to the top bar of the sash 11 as by means of staples 49 suitably secured to the latter. Enveloping the spindle 45 and anchored at. its opposite ends in the adjacent faces of the pulleys 47 is a torsion spring 50. By reason of the fact that one of the pulleys a7 is connected to one end of the spring and the other to the other end of the spring, the stress imparted by the spring acts at both ends of the latter independently on the pulleys, and therefor-stakes up automatically any slack or lack of equality of tension in or upon the straps 4S, and insures an equal sides of the sash. result is obviously attained also in the constructions disclosed in the embodiments of the invention previously described.

It will be noted that in the construction set forth in Figs. a and 5 a spring of comparatively large diameter is employed in connection with relatively small gearwheels 18; while in the construction disclosed in Figs. 6 and 7 a spring of relatively small diameter is employed in connection ith relatively large gears. "Where there is room for a relatively wide sash balance the construction of Figs. 4 and 5 may be employed, the larger diameter of spring perniitting a relative diminution in the diameter of the gears; whereas, where the lateral space for the sash balance mechanism is limited, :1- smaller spring and rendered effective through the employ ment of relatively large gears, which obviously do not require as many turns to tension the spring as do the relatively smaller gears.

The capability of the mechanism to permit tensional adjustment of the spring Without necessitating any removal of the mechanism from its casing or from the window constitutes an important feature ofthe in vention; and it will be evident that the structural features herein disclosed may be considerably modified and varied by those skilled in the art without departing from the principle or sacrificing any of the advantages of the invention.

I claim:

1. In a sash balance, the combination of a sash, a torsion spring, reversely rotatable power'transmitting members connected to and independently actuated by the opposite ends of said spring respectively, and con- This latter may be employed 7 nections between said powertransmitting members and the sash whereby an equalization of the action of said spring on said sash is secured, substantially as described.

2. In a sash balance, the combination of a movable sash and its frame, a torsion spring, and reversely rotatable members fastened to opposite ends of said spring and operating along the vertical walls of said frame for actuating the sash, substantially as described.

8. In a sash balance, the combination of a movable sash and its guides. a torsion spring, and means for equally balancing said sash including oppositely rotatable mem bers acted'upon by the opposite ends of said spring and oppositely rotatable in planes transverse the axis of the spring, substantially as described.

4. In a construction of the character described, the combination of a sash frame, a sash movable in said frame, a torsion spring, independently operable power-trans mitting members secured to opposite ends of said spring in engagement with the frame and adapted to cause an equal balancing of said sash, substantially as described.

5. In a sash balance, the combination with a sectional spindle having an interposed torsion spring and a coupling member, the latter constituting also tensioning members for said spring, of gears on the ends of said spindle, and diagonally disposed racks engaged by said gears, substantially as described.

6. In a sash balance, the combination with a sectional spindle and an interposed torsion spring, of a cooperating Worm-wheel and Worm on adjacent ends of adjacent sections of the spindle, said worm-wheel and worm constituting tensioning members for the spring and a coupling for the spindle sections, gears on the ends of said spindle,

and diagonally disposed racks engaged by said gears, substantially as described.

7. In a sash balance, the combination with a movable sash and its frame, of a torsion spring, a pair of oppositely rotatable pinions connected one to each end of the spring, and oppositely facing racks carried by the frame each in mesh with one of the pinions, substantially as described.

8. In a sash balance, the combination with a movable sash and its frame, of a torsion spring, a pair of oppositely rotatable pinions connected one to each end of the spring, oppositely facing racks carried by the frame each in mesh with one of the pinions, and an adjustable connection be tween one end of the spring and its pin ion whereby to regulate the tension of the spring Without disturbing its sash balancing function, substantially as described.

9. In a sash balance, the combination with a movable sash and its frame, of a torsion spring, rotatable members connected to the ends of the spring and engaging the frame, and a gear connection between the end of the spring and one of the rotatable members whereby to angularly adjust the same, substantially as described.

10. In a sash balance, the combination with a movable sash and/its frame, of a torsion spring, rotatable members engaging the frame, and a connection between one end of the spring and one of the driving members whereby to angular-1y adjust the same to regulate the tension of the spring, said connection comprising a spindle arranged axially of the spring, a wornrwheel thereon, a disk mounted on the shaft of the rota-table member, and a WOI'lll journaled in the disk in mesh With the Worm vheel, the

Worm provided With eXtel'iorly accessible means to, rotate'the same, substantially as described, I

11. In a sash balance, the combination of a sash, a torsion spring, reversely rotatable power-transmitting members connected to sash is secured, and means for adjusting the tension of the spring, substantially as described.

'12. In a' sash balance, the combination of i a movable sash and its frame, a torsion spring, and reversely rotatable members fastened to opposite ends of said spring and operating along the Vertical Walls of said frame for actuating the-sash, and means for adjusting the tension "of'the spring, sub sta'ii'tially as described' GEORGE H. FORSYTH. Witnesses: SAMUEL N. POND, I

' FREDERICK C. GooDWIrI'.

Copis of this patent may be obtained for flire cents each; by addressing the c niiiiisgieiir' o1 fiuiigii;

Washington; D. G. 

